Improvement in lamp-chimneys



R. N. EAGLE. V Lamp Chimney,

Patentedlan. 18, 1870.

' [72 am? far.

ROBERT N. EAGLE, OF WASHINGTON, DISTRIOT OF COLUMBIA.

Letters Patent No. 98,936, dated January 18, 1870.

IMPROVEMENT IN LAMP-CHIMNEYS.

The Schedule referred to in these Letters Patent and making part of the same To all whom it may concern:

Be it known that I, ROBERT N. EAGLE, of Washington, in the'District of Columbia, have invented new and useful Improvements in Lamp-Chimneys; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the annexed drawings, making part of this specification, in.whicl1--- Figure 1 is an elevation.

Figure 2 is a side elevation.

, Figure 3 is a plan. v

Figure 4 is a transverse section.

This invention relates to improvements in that class of chimneys which is in common use on kerosenelamps.

My improvements consist in-- First, a modification in the form of the chimney, de-

' signed to increase the intensity-of the light, and allow of and sustain a freer and more natural spread of the flame, thereby removing one great cause of the liability to breakage of 'the chimney; and

Secondly, in forming upon the edge of a' flat chimney aseries of bead-like projections, formed by depressions cut in the mould, at the seam where the two parts of the mould join.

In the annexed drawings- A represents the base of the chimney, of a form and size to adapt it to the burner upon which it is to be'placed.

The throat, or base deflector, is formed in the ordinary manner, by converging the sides at B, for the purpose of diverting the ascending currents of air, and

directing them against the flame, thereby to increase its intensity. I

Above the throat the body 0 is expanded, so as to acquire an oval form, as shown in the drawings. The longest diameter of the body should be such as to afford a free and natural expansionot' the flame, without bringing the edges thereof in such near proximity to the glass as to produce fracture, or to chill the ascend.- ing gases, and cause themto smoke .the insideof the chimney.

From the point where the body, in expanding, at-- tains its fullest width, which should be opposite what would he the widest pelt-0t the flame, it is extended upward, still preserving, or nearly preserving, in its general outline or profile,'its longest diameter, nearly to the top, as shown in fig. 1, but tapering slightly in the direction of its shortest diameter, as shown in fig. 2, until it reaches the point D, where is suddenly contracted, forming a more or less abrupt shoulder in the line of its longest diameter, and terminating in a more or less flattened elliptical mouth orneck, E, such mouth or neck being carried to any desired height above the shoulders, according to theintensity it is intended to give the draught.

' Theeflect of the shoulders, at D, is to form what I -call dead-air recesses, in which will be detained, as it flows through the chimney, air, in sufficient quantity, and so conditioned, as that with the'assistance of the super-deflector, hereinafter referred to, the intenser heat arising from the flame shall be prevented from acting in full force directly upon the shoulders D or mouth E, at both of which points a chimney is especially liable to fracture, from the effect of sudden contraction and expansion.

\Vhile thus contracting in the line of the longest diameter of the ellipse, I prefer to slightly increase the diameter in the direction of the short axis of the f ellipse, as shown in fig. 2.

l have shown the mouth or neck E as being slightly oval, which form I prefer for the style of chimney shown, but it may, without endangering the effectiveness of the chimney, or departing from the principle of my invention, be either-more elliptical, as indicated indotted linesin fig. 3, orround, as in ordinary chimneys.

It will be observed, also, that the chimney, while parallel or gradually tapering on the sides or edges, to y the shoulder atD, has also its flattened faces convergin g to a line horizontal with the shoulders, and breadthwise across the chimney, at or below the point of the shoulder I). The sides of the chimney at this section should be flat, or but slightly convex.

This convergence of the flattened faces of the chimney, at or near the point above designated, I will'call the super-deflector, inasmuch as by such convergence- .or depression of the faces toward each other a throat is formed, through which, as has alreadybeen described, in connection with the shoulders D, the heated currents, in their ascent, are deflected toward the shoulders, and thus diverted in their passage to the mouth or exit apertures.

In constructing chimneys which are blown in moulds,

or made after the manner of pressed glass, Ipropose toform, upon the edges of the flat portion of such chimneys, rows of bead-like concavo-convex protuberances, formed by cutting depressions in the mould, where the two parts which formfthe mould meet. These protuberances may be of any form, according to fancy, and those in thebase of the lamp may be formed to receive springs upon the lamp-burner, to hold the chimney inits proper, position in relation to the flame of the lamp.

I am aware that such protuberances have been introduced into the modes of ornamenting chimneys, and I therefore do not claim them broadly, but only the prescribed arrangement upon the edges of a. flat chimney, or on the base, in line with the flat flame.

I am aware, also, that chimneys are in use, the body of which is elliptical, and which, from the point of its greatest breadth, is contracted to terminate in an elongated cylindrical neck or mouth; but my improved chimney differs from them in this: that the body, from the point of its greatest breadth, (at or about on a line horizontal with the top of the flame,) is carried upward to the top, or nearly to the top of 'the' chimney, still preserving, or nearly preserving the same breadth as below; or that, in other words, the body is elongated in directionof its height, with sides either parallel or but slightly contracted, to a point near the top of'the chimney, and thence, from the point at D, abruptly contracted toward the neck or base of the mouth E, forming a shoulder on either side of the said neck, substantially such as shown, it being observable that the neck or mouth Emay be more or less extended above such shoulders, as may be desirable for intensifying the draught.

. By this mode of constructing the upper part of a chimney, a proper breadth of draught is secured, to insure equal combustion to all parts of the wick, and

a fuller spread of the flame secured and maintained,

without impingement of the flame at the sides or edges of the chimney, to cause smoking or fracture, or of inclining the flame to burn centrally, as when the neck or terminating-mouth gradually tapers from a greater breadth below, to an exit-aperture placed opposite to the centre of the bulge, or widest part of the chimney below, as is the case ofordinarily-constrncted chimneys.

. Having thus described my invention,

What I claim as new, and desire to secure by Letters Patent, is Y 1. A glass chimney, the elliptical body of which is elongated, with parallel or nearlyparallel sides, abruptly contracted at E, forming shoulders on either side of the neck or mouth E, substantially as shown and set forth. 2. A glass chimney, with an elliptical body extended in the direction of its height, and terminating in a month, which has a greater diameter in the direction of the depth or thickness of the chimney than has the body 0 at a point immediately below such month or neck, as shown in fig. 2. 3. A glass chimney, the parts shown at A, B, O, D, and-E of which are respectively formed, substantially as set forth. l

4. A lamp-chimney, having rows of concavo-eonvex bead-like protuberances placed along the seam formedv by the joints of the mould, and in the vertical plane of the flame, substantially as set forth..

5. A flattened chimney, having shoulders at D, to

form dead-air recesses, substantially as set forth. 6. A glass chimney, the sides or edges of which are parallel or gradually converging, and the flattened faces of which are also converged, to form a super-deflector below the mouth, substantially as set forth.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses. 4 i

R. N. EAGLE.

Witnesses R. MASON, B. H. J omssron. 

